The study by American chemist Ronald Breslow, at Columbia University, is actually about the conditions that made life possible on earth. But its conclusions are stunning: ‘An implication from this work is that elsewhere in the universe there could be life forms based on D-amino acids and L-sugars,’ writes Breslow. ‘Such life forms could well be advanced versions of dinosaurs, if mammals did not have the good fortune to have the dinosaurs wiped out by an asteroidal collision, as on Earth. We would be better off not meeting them.’
Breslow maintains that the origin of terrestrial prebiotic homochirality, a condition for life to start anywhere, is on meteorites that fell to earth about 4 million years ago. These meteorites brought amino acids that eventually would have led to the D-sugars that can be found in DNA.
This finding is what makes Breslow think that there might be intelligent life on other planets, an advanced version of our dinosaurs. The study, published online in the Journal of the American Chemical Society, is still pending technical editing, formatting for publication and author proofing.
Breslow R (2012). Evidence for the Likely Origin of Homochirality in Amino Acids, Sugars, and Nucleosides on Prebiotic Earth. Journal of the American Chemical Society PMID: 22444622